Volcanoes emit much hydrogen sulfide gas, h2s, which reacts with the oxygen in the air to form water and sulfur dioxide, so2. every 72 tons of h2s reacts with 101 tons of oxygen and forms 38 tons of water. how many tons of so2 are formed?

135 tons of are formed

Explanation:

Every 72 tons of reacts with 101 tons of and forms 38 tons of and x amount of .

As per as law of conservation of mass:

Total mass of reactants = Total mass of products

72 tons + 101 tons = 38 tons + x

x = 135 tons

135 tons of are formed

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !